'Declaration
 
<ExtensionAttribute()>
Public Overloads Shared Function SubscribeItem( _
   ByVal client As IEasyDAClient, _
   ByVal machineName As String, _
   ByVal serverClass As String, _
   ByVal itemId As String, _
   ByVal requestedUpdateRate As Integer, _
   ByVal state As Object _
) As Integer

'Usage
 
Dim client As IEasyDAClient
Dim machineName As String
Dim serverClass As String
Dim itemId As String
Dim requestedUpdateRate As Integer
Dim state As Object
Dim value As Integer
 
value = IEasyDAClientExtension.SubscribeItem(client, machineName, serverClass, itemId, requestedUpdateRate, state)

[Extension()]
public static int SubscribeItem( 
   IEasyDAClient client,
   string machineName,
   string serverClass,
   string itemId,
   int requestedUpdateRate,
   object state
)

[Extension()]
public:
static int SubscribeItem( 
   IEasyDAClient^ client,
   String^ machineName,
   String^ serverClass,
   String^ itemId,
   int requestedUpdateRate,
   Object^ state
) 

Parameters

client

The client object that will perform the operation.

This is typically the EasyDAClient object.

The value of this parameter cannot be null (Nothing in Visual Basic).

machineName

Name of the machine (empty string for local computer).

The value represents a UNC or DNS computer name. Any string can be passed to this parameter (i.e. will not cause System.ArgumentException), but not all values make sense and will work when an operation using them is attempted. IPv6 addresses are normally enclosed between '[' and ']'.

The value of this parameter cannot be null (Nothing in Visual Basic).

serverClass

Contains ProgID of the OPC server.

The value of this parameter cannot be null (Nothing in Visual Basic).

itemId

ID of the item that will be subscribed to.

The value of this parameter cannot be null (Nothing in Visual Basic).

requestedUpdateRate

How often should the updates be received (number of milliseconds)

state

The state object (can be any object supplied by your code); available in event notifications.

The value of this parameter can be null (Nothing in Visual Basic).

Return Value

This is an extension method (info: C#, VB.NET). In languages that have support for extensions methods (such as C# and VB.NET), you can use the extension method as if it were a regular method on the object that is its first parameter. In other languages (such as with Python.NET), you will call the extension as a static method, and pass it the object on which it acts as its first parameter.

Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2016, Windows Server 2022; .NET: Linux, macOS, Microsoft Windows